摘要:
Performance of a radio device is optimized by estimating if the device is inside a building. One or more sensors on the radio device are used to measure an environmental quantities relating to the environment of the radio device. The likelihood of the radio device being inside a building is inferred from these measurements. The operation of the radio device then is controlled accordingly. For example, if the radio device is determined to be inside a building, a low operating frequency may be selected for the radio device if a wide area network connection is required, while a high operating frequency may be selected if a local connection is required. An environmental quantity may be, for example, a satellite signal, ambient light, temperature, RF energy, or the response to a test signal emitted by the radio device.
摘要:
In a cognitive radio, a method of establishing an operational policy for use in a Peer-to-Peer (P2P) group, wherein the policy can be described by layers of policy parameters with progressively higher layers having a progressively increasing number of parameters, involves determining that a policy change is to be made from a current policy; requesting policy information from at least one P2P group member; receiving a policy description from the at least one P2P group member; and implementing a change in the lowest layer policy parameter to establish a new operational policy.
摘要:
In certain embodiments, a method for managing operational parameters of a cognitive radio device to minimize non-compliance with a regulatory policy involves sensing a change in an operational condition that will affect compliance with a current operational policy; estimating a time at which the current operational policy will become invalid; selecting a method for determining how to update the current operational policy; and updating the current operational policy of the cognitive radio device. Other embodiments may incorporate more, fewer or other elements.
摘要:
A method and apparatus for reducing inter-modulation within a wireless communications device (100) is provided herein. During operation a wireless communications device will perform frequency analysis on a received signal (125) to determine if any undesirable IM products exist. If undesirable IM products exist, the incoming signal is attenuated by adjusting an automatic-gain control (AGC) threshold for AGC circuitry (101, 107). By adjusting the AGC threshold, the incoming signal will be attenuated at lower gain values, reducing the amount of IM present within the wireless communications device.
摘要:
An adaptive graphic equalizer (200, 400) has various ordinarily fixed parameters (such as center frequencies, filter bandwidths, and step response sensitivity) that are automatically altered to suit a particular audio source. In one embodiment, a radio (100) includes the graphic equalizer, and such adjustments are automatically made depending upon whether the user has selected the AM or FM reception band.
摘要:
An improved AM-FM combined stereo receiver is provided having a single processor for removing, in the FM mode, arctangent distortion, and in the AM mode, to process the phase term from arctangent ##EQU1## to determine ##EQU2## Further, the radio includes a single discriminator circuit wherein, in the FM mode, the discriminator tank circuit is used to convert frequency deviation to baseband audio and, in the AM mode, the discriminator tank circuit is used as the frequency-determining element for the voltage controlled oscillator (VCO), the VCO being used to translate the intermediate frequency (IF) signal to baseband.
摘要:
A circuit for use in a phase locked loop (PLL) which is responsive to the PLL being out of lock for providing fast lock current to drive the VCO of the PLL in the direction to acquire lock. The circuit includes a pair of controlled current sources responsive to selective control signals for either sourcing or sinking fast lock current at the output of the circuit that are utilized to produce an error control voltage at the loop filter to drive the VCO accordingly while a reducing circuit is responsive to the control voltage reaching a predetermined value as the VCO is driven toward one end or the other of its range for clamping the control voltage while reducing the fast lock current to a reduced value thereby limiting excessive charge build-up on the loop filter capacitor of the PLL. Thus, the circuit permits the VCO to acquire fast lock up by providing fast lock current thereto while clamping the range of the VCO and reducing the fast lock current as the VCO approaches either end of its range. Upon acquiring lock up, the controlled current sources are disabled.
摘要:
An improved radio receiver that maintains a stable predetermined IF frequency upon receipt of input carrier signals of differing frequencies. The IF signal (14) is processed through a signal demodulation unit (16) that includes a tangent processing unit (22) to yield a control signal that varies as a tangent function of both the demodulated IF signal and a reference signal from a reference oscillator (17). This control signal is used to control the frequency and phase of a reference signal (26) used by the IF stage (12) to center the IF signal with respect to the IF stage characteristics.
摘要:
A linearized differential amplifier having two feedback paths. One of the feedback paths functions to linearize the output of the differential amplifier. The remaining feedback path functions to slightly limit the operating range of the differential amplifier to ensure the operational stability of the differential amplifier.
摘要:
A correction control circuit for use in compatible AM stereophonic receivers of the type utilizing a cosine correction signal to remove inherent distortion from the received and detected signals. During periods of weak or noisy signals or when co-channel interference is present, excess cosine correction signal causes a reduction in the amount of stereo difference signal component in the output signals, and in the amount of correction provided. In a worst case signal situation, there will be no difference signal component in the output and the monophonic output not be corrected.